Goodman GCES801005C furnace filter size
This furnace takes 2 filters, each 14 x 20 (downflow top return) or a 20 x 25 filter (downflow top return), depending on where the return air comes in.
The maker lists width and height only. Most filter racks next to a furnace hold a 1-inch filter; a separate filter cabinet usually holds a 4- or 5-inch one. Check the thickness printed on the edge of your old filter before you order.
Every filter option for this model
Where the filter goes
Not supplied. Quote: "Filters do not ship with this furnace, but must be provided by the installer." (IOG-2021B / SS-GMES80). IO: "Larger filters may be used, filters may also be centrally located"
The maker does not ship a filter with this furnace. The size above is the maker's recommended size at the furnace; if your home has a filter grille in a wall or ceiling, that grille sets the size instead.
How often to change it
General guidance, not from the maker's table: 1-inch filters every 1 to 3 months; 4- and 5-inch filters every 6 to 12 months. Change sooner with pets, smoking or construction dust.
About this model
| Cabinet width | 21 in. |
|---|---|
| Airflow direction | downflow/horizontal |
| Heat input | 100,000 BTU/hr |
| Efficiency (AFUE) | 80% |
| Model number note | * in the doc = NOx/gas letter (N, X) plus revision letters (e.g. GM9S800603AN, GM9S800805CXA) |
How to read a Goodman model number
Source
- SS-GMES80/GCES80 Product Specifications, rev 6/19 (spec sheet, page 16): document. Read 2026-11-03.
- IOG-2021B Installation Instructions *MES80*N/X & *CES80*N/X Gas Furnace (2019) (installation manual, page 18): document. Read 2026-11-03.
Check that the model number on your furnace label matches, and compare with the size printed on your old filter. If they differ, go by the filter that fits your rack.